Why is the communication ability so strong? Is the coronavirus finally a variant? The four mysteries of Omikeron are revealed

During the surge in infections in Omikejong, a health worker prepares a vaccine. Image credit: Nature website

In humans, Omikeron seems to be highly contagious, but the symptoms are not as good as other variants, why is it like this? How does it interact with host cells and the immune system? Answering these questions could help lead to better drugs or vaccines, and provide clues as to whether the coronavirus will continue to change and new variants will emerge. In a recent report by the British magazine Nature, it solved four mysteries about Omikejong.

Why is the communication ability so strong?

The rapid spread of Omikeron is largely due to its possession of dozens of mutations that distinguish it from previous variants and allow it to avoid antibodies in the host, specifically neutralizing antibodies that bind to spike proteins on the periphery of the virus and prevent the virus from entering the cell. This means that while many people already have extensive immunity to earlier versions of the coronavirus, There are more hosts to choose from than the Delta variant. In addition, some of the characteristics of the Omiljung itself may also make it highly contagious.

In terms of viral transmission, one view is that this variant produces a higher concentration of viral particles in the nasal cavity, so infected people exhale more virus each time they exhale, but scientists have not reached a consensus on this.

A study of human lung and bronchial tissue by michael Chang, a virologist at the University of Hong Kong, supports this speculation. Their data suggest that Omiljung replicates in the upper respiratory system faster than all previous variants of the coronavirus. The team of Wendy Barkley, a virologist at Imperial College London, found that Omikeron copied faster in cultured nasal cells than Derta.

But some studies have reported that immunocompromised hamsters have fewer Particles of Theomilon virus in their lungs than previous variants, and none of them are contagious. Some studies in humans have shown that Omexron produces the same or lower concentrations of infectious viral particles in the upper respiratory tract as Delta.

Buckley thinks the intensity of Opmirkjong's spread may have something to do with how it gets into cells. Early versions of the coronavirus relied on the cell receptor ACE2 to bind to the cell and the TMPRSS2 cellular enzyme to break down its spike protein, allowing the virus to enter the cell. But Omikeron essentially gave up TMPRSS2, and the cell would swallow it whole, and it would burrow into an intracellular vesicle called an endosome.

Buckley said that many cells in the nose produce ACE2 rather than TMPRSS2, which may help Omilon begin to function after being inhaled and before it reaches the lungs and other organs that commonly express TMPRSS2, which may partly explain why Omilon is so capable of transmitting.

Why aren't the symptoms severe?

Judging by the hospitalization rate and mortality rate, Omi kerong seems to be weaker than the previous variant. But given that many people have some degree of immunity through vaccinations or previous infections, scientists hope to figure out to what extent it "weakens" because many people's immune systems are already able to cope with the virus; to what extent it is because of the virus itself.

Scientists at Case Western Reserve University School of Medicine in Cleveland distinguish these two factors by studying the first infection in children under 5 years of age (these children have not yet been vaccinated), and the symptoms of infection with Omicron are milder than those of Delta in terms of emergency room attendance, admission rate or intensive care unit and demand for ventilators. In another study, South African scientists analyzed the risk of hospitalization and death in adults in the early stages of Aomi Kerong infection, and 25% of the factors that reduced the severity of symptoms of surface infection were due to the characteristics of the virus itself.

What makes Amikeron's "fangs" "blunt"? Michael's team found that although the variant replicates faster in the upper respiratory system, it has a weaker ability to replicate in lung tissue. Studies of rodents have found that Omilton infection has less inflammation and damage to the lungs. For humans, The Opmikron has less ability to multiply or cause damage to the lungs, fewer cases of severe pneumonia and dyspnea, and more cases of nasal cold.

Barkley said another reason for the reduced severity of symptoms from infection with Omicron may be its inability to fuse individual lung cells into larger syncytia — as previous variants of the coronavirus could have been. Some scientists believe that this aggregate can trigger symptoms or help the virus spread.

How to deal with Aomi Kerong?

One of the body's key "weapons" against pathogens is a molecule called interferon, which is produced when cells detect a virus invasion. Interferon tells infected cells to strengthen their defenses, and also sends warning signals to uninfected neighboring cells to strengthen their defenses as well.

Previous variants can avoid or inhibit many of the effects of interferons. Some studies have shown that while Omiqueron loses some of its advantages, it is better able to resist the effects of interferons.

Researchers are also studying the parts of the virion that attract the attention of T cells. Viral proteins that can be recognized by T cells don't seem to change much in Omexjong compared to previous variants — good news because while T cells respond more slowly to recurring threats than antibodies, they are very effective once they start acting, which helps prevent symptoms of infection from getting worse.

Understanding which parts of the coronavirus rarely mutate and activate the T cell response could help scientists develop new vaccines that induce T cells to fight current and future viral variants.

What happens next?

Data to date suggest that Omiqueron may be highly contagious early in the course of infection, but when they try to spread beyond the upper respiratory tract or are blocked by interferons, the number of viruses and their ability to infect other cells or humans decline rapidly.

Although the severity of the symptoms of the Omiljunn infection has been drastically reduced, most experts believe it will not be the ultimate variant.

Jesse Brom, an evolutionary virologist at the Hutchinson Cancer Research Center in the United States, said that there may be two scenarios in the future: one is that TheOmilon continues to mutate, producing a worse Version of the Omiljung+ variant; the other is the emergence of a new variant that is not related to the Omiljung.

Lucy Thorne, a virologist at University College London, said scientists were concerned about the second scenario, which suggests the virus is highly adaptable and that "it has more than one evolutionary choice". With dozens of variants, Omilon has a larger evolutionary space than the other variants, and many of its variants, though weaker, bloom everywhere. In addition, scientists suspect that Omikeron may penetrate into more species and then spread back to humans again, bringing new dangers.

(Science and Technology Daily)